One-step transfistula large versus conventional balloon dilation following precut fistulotomy in difficult biliary cannulation for the removal of biliary stones: a multicenter retrospective study

Is the Isolated-Tip Needle-Knife Precut as Effective as Conventional Precut Fistulotomy in Difficult Biliary Cannulation?

Background/Aims

Needle-knife precut fistulotomy (NK-F) is a well-known freehand technique for difficult biliary cannulation (DBC). Another approach involves the use of Iso-Tome^®, a modified precutting device with an insulated needle tip to prevent direct thermal injury. This comparative study aimed to evaluate the efficacy of the Iso-Tome^® precut (IT-P) compared to that of NK-F for DBC.

Methods

Patients with a naive papilla who underwent early IT-P or NK-F for DBC were enrolled. DBC was defined as failure to achieve selective biliary access by wire-guided cannulation despite 5 minutes of attempted cannulation, ≥5 papillary contacts, or a hook-nose-shaped papilla. The primary endpoint was the primary technical success rate, which was based on a noninferiority model.

Results

A total of 239 DBC cases were enrolled. The primary technical success rates were 74.7% (89/119) in the IT-P group and 91.6% (110/120) in the NK-F group (lower limit of 90% confidence interval, −0.23; p=0.927 for a noninferiority margin of 10%). The total technical success rates were 87.4% and 95.0%, respectively (p=0.038). The mean precutting times for successful biliary access were 11.2 minutes for IT-P and 7.3 minutes for NK-F (p<0.01). The procedure-related adverse event rates were 9.2% for IT-P and 5.8% for NK-F (p=0.318). The rates of post-endoscopic retrograde cholangiopancreatography pancreatitis were 4.2% and 2.5%, respectively (p=0.499).

Conclusions

IT-P failed to exhibit noninferiority compared with NK-F regarding the primary technical success rate of DBC, but there was no difference in the frequency of adverse events.

Difficult Biliary Access: Advanced Cannulation and Sphincterotomy Technique

Many devices and techniques have been developed to assist in cases of difficult biliary cannulation. Guidewire-assisted cannulation has become the first-line technique for biliary cannulation. Precut sphincterotomy can be safe and effective if used soon after encountering difficulty. Pancreatic duct stents are an important adjunct to reduce the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis in difficult access. Ultimately, cannulation success of greater than 95% and complication rates of less than 5% is the standard that endoscopists doing ERCP should achieve.